The main objective of this research project is to apply recent advances in cellular immunology and immunochemistry to problems related to diseases of the periodontium. Specifically, we seek to: (1) characterize the inflammatory cell infiltrate found in normal and diseases gingiva using cell membrane markers, (2) demonstrate de novo biosynthesis of immunoglobulins complement and other proteins associated with the inflammatory response in the gingiva and (3) ascertain the specificity(ties) of the antibody produced in the gingiva. Normal gingiva and gingiva from patients with periodontal disease will be digested with collagenase and the cells recovered via Ficoll-Hypaque separation. These isolated mononuclear cells will be characterized by spontaneous E rosetting, surface immunogLobulin, Fc receptors, C3 receptors and blastogenesis with both T and B cell mitogens. We will attempt to demonstrate biosynthesis in the gingiva of immunoglobulin isotypes, complement components and other proteins associated with inflammation using 14C labeling in vitro. We will test the possibility that at least a portion of this locally synthesized antibody is directed against plaque microorganisms. We plan to use a variety of methods in determining the antibody specificity. Since the chronic inflammatory infiltrate is a cardinal feature of periodontal disease a study of this local immune response in periodontal disease is imperative. Identification of the specific immunologic mechanisms involved will play a key role in the prevention and treatment of the disease.